A Position-and-Velocity Sensorless Control for Brushless DC Motors With an Adaptive Sliding Observer

Abstract

It has been known that a state equation of a blushless DC motor is a nonlinear one. Recently, new linear state equation and a position and velocity sensorless control system with the full-order observer based on the equation has been proposed. But the pole assignment of the observer has not been presented clearly. In this paper, we propose an adaptive sliding observer for this linear state equation and present clearly the pole assignment of the sliding observer for robust flux estimation with estimated velocity error. The simulation shows that the proposed system is very useful.